The present invention relates to a handhole, a manhole or the like for use as an electric wire junction when an underground conduit line is formed for an electric wire, and to a tubular body to be connected to such a handhole or a manhole.
Conventionally, in order to form an electric wire conduit line by coupling a tubular body to an electric wire junction such as a handhole, a manhole or the like of the sort mentioned above (hereinafter generally referred to as a handhole), it has been arranged that a tapered tubular member called a bell mouth separately formed is inserted in and coupled to the opening of the tubular body so as to use the bell mouth as a member forming the end of the opening of the tubular body.
The operation of passing the electric wire through the tubular body has been impossible to perform smoothly unless the bell mouth is inserted in and coupled to the opening of the tubular body because the electric wire is brought into contact with the peripheral edge portion of the opening of the tubular body with the result that the resistance increases. Therefore, it has been necessary to prepare the bell mouth separately from the tubular body used to form the conduit line and transport the bell mouth to the jobsite. Moreover, the operation of coupling the bell mouth to the opening of the tubular body is necessitated in order that the bell mouth is not easily slipped off the opening thereof.